U.S. Pat. No. 5,078,167 to Brandt et al discloses a fuel filter and pressure regulator system which has been well accepted by the automotive industry. One of the disadvantages with such a device however is that if the filter becomes clogged, the entire unit including the pressure regulator portion needs to be replaced and likewise if for some reason the pressure regulator were to malfunction, the whole unit, including the filter, needs to be replaced. Consequently, there is a need for a device like that shown in U.S. Pat. No. 5,078,167 which is modular so that the filter unit and regulator unit can be separately and independently replaced without replacing the other one thereof. It is however still desirable to have the units together on top of the fuel tank of a vehicle and consequently there has existed a need to solve the problem of how this should be done.